YELLOWSTONE NATIONAL PARK, Wyo. (AP) – A park official Wednesday said that an autopsy revealed that a man whose body had been found by Yellowstone National Park’s shores died from hypothermia.
Mark O’Neill, age 67, was from Chimacum, Washington. He had been on a four night backcountry trip to Shoshone lakes with his brother Kim Crumbo, who is from Ogden, Utah. They were reported missing by a relative on Sept. 19.
O’Neill’s body was found by searchers on Sept. 20, at the lake’s eastern shore. Park officials stated that Crumbo will be searched on foot and by boat, weather permitting, for several more days.
A campsite that was vacant was found on the lake’s south side. They said that they are still investigating the incident.
Crumbo, a former Navy SEAL and experienced boater, was also a Vietnam veteran.
Crumbo founded the Grand Canyon Wildlands Council conservation group, which was later merged to form Wild Arizona.
Shoshone Lake is 13 miles (33.3 km) in area and has an average temperature 48 degrees Fahrenheit (9 Celsius). Officials said that those without insulating gear are typically unable to survive in this cold water for more than 20 to 30 minutes.